Field of the Invention and Description of the Prior Art
This invention relates to an improved assembly for dividing a continuous film strip containing a plurality of longitudinally spaced articles into a plurality of individually sealed packages, and it particularly relates to an improved apparatus for forming individual packages for a tubular plastic film wherein the packages contain an individual serving of crackers, cookies or the like and wherein each of the formed packages includes a slit in the outer portion thereof in order to provide for easy opening of the package.
It is common in the food industry, in particular, to package various products in individual packets or packages. Such packets are commonly used to package crackers, cookies, and similar products in individual servings. These packages are generally formed from a tubular plastic film, such as cellophane or polypropylene, and generally contain two crackers or the like therein. The packages are commonly used by restaurants and institutions.
For many years, these packages of crackers or the like were manufactured from cellophane. In the past several years, however, because of increased cellophane prices and questionable future availability, suppliers have converted from the use of cellophane film to polypropylene film in order to wrap the same products. The use of polypropylene, however, has raised various problems, including manufacturing or operational problems and marketing problems. The operational problems included closer heating and cutting tolerances required for polypropylene relative to cellophane.
A significant marketing problem with a polypropylene film package involves the nature of polypropylene film, that is, the polypropylene packages are more difficult to open than cellophane packages to which customers have been accustomed. One of the reasons for the difficulty in opening the polypropylene film packages is that polypropylene has a more narrow heat control range than cellophane and polypropylene tends to "bead" or melt slightly along the cut edge.
One typical machine used for forming packages from cellophane involves a method and apparatus for forming cellophane around the product, such as crackers, in a tubular fashion with the products being longitudinally spaced so that they can be crimped, sealed and cut into separate packages. The machines conventionally used a pair of rollers having heated crimpers thereon, utilizing reciprocal, cam activated hack saw blades, for transversely cutting the tubular strip. In order to solve the problem of opening the polypropylene package, a machine for forming a slit in the outer edge of the package is considered to be highly advantageous.